Tokyo Tech News

Method established for detecting "Negative Hydrogen" H− ions in solids


Published: October 23, 2014


Associate Professor Katsuro Hayashi, of the Materials and Structures Laboratory at the Tokyo Institute of Technology's Center for Secure Materials, and a research group including Professor Hideo Hosono, of the Tokyo Institute of Technology's Frontier Research Center, succeeded in establishing a method for the easy identification of "Hydrogen with a negative electric charge" (Hydride H ions) formed in solids using nuclear magnetic resonance (NMR) alone. It was realized from the discovery that NMR observation limits can be compensated for by creating a correspondence with the size of the space around hydrogen in substances. Using this they provided the world's first proof that H ions are formed in apatites, which are substances in the composition of teeth and bones.

The same group has been involved in research on H in solid materials in order to obtain improved transfer temperatures in iron superconductors and transparent conductive membranes on cement material matrices. However, in order to actually prove the existence of H, experiments at large-scale research facilities and the accumulation of a large amount of indirect experimental evidence was required, which also necessitated a great deal of labor. With the current establishment of an effective method to clarify the unknown H, the expectation is for the accelerated development of new functional materials including H ions.

The results of this research appeared in the English scientific journal "Nature Communications" published on March 24th.

This work was supported by MEXT Element Strategy Initiative to form a core research center in Japan.

Localized structure incorporating apatite ceramics and H- ions.
Localized structure incorporating apatite ceramics and H ions.
Everything other than the red signal is caused by H+ (OH) in a variety of states.


Katruro Hayashi, Peter V. Sushko, Yasuhiro Hashimoto, Alexander L. Shluger, Hideo Hosono
Title of original paper:
Hydride ions in oxide hosts hidden by hydroxide ions
Nature Communications, 3515 (2014).

Further information

Professor Hideo Hosono
Frontier Research Center, Tokyo Institute of Technology

Associate Professor Katruro Hayashi
Secure Materials Center, Materials & Structures Laboratory, Tokyo Institute of Technology

Now at:
Department of Applied Chemistry, Kyushu University